1. Field of the Invention
The recent past has seen a widespread interest in feeding backyard birds. Accompanying this activity has been the construction and engagement of bird feeders that dispense seeds as feed for these wild birds. Certain species of these birds, notably the introduced house sparrow, the introduced European Starling, and the transported house finch, tend to dominate such feeders. Not only do they overpower and outnumber the native birds, but they also have voracious appetites, consuming large quantities of seed. This requires numerous trips to fill the feeder and, likewise, a large feeder compartment to accommodate a large volume of seed. This invention relates to a device design that restricts the use of the feeder to the overpopulated house sparrows and starlings and allows access to the native birds that have an ability to cling.
2. Description of the Prior Art
While the need to provide a feeder that is more favorable to native birds exists, either insufficient attention has been devoted to the subject or prior efforts have proven inadequate. U.S. Pat. No. 3,022,768 by Lynch demonstrates a feeder having a wall formed with a plurality of "upwardly extending slots which are not wide enough to permit feed to drop" from the hopper by gravity, "but are wide enough to permit the feed to be picked through the slots by birds of the `clinging` type such as chickadees, woodpeckers, resting on portions of the wall between the slots which portions thus function as support elements for such birds". This feature foils birds such as English sparrows that cannot cling.
While the concept presented by Lynch is noteworthy, it has certain inherent misgivings. Once a chickadee or woodpecker has gained a foothold on a surface and has made its initial clinging retention, it is then easy for it to negotiate around awkward positions. But it first must be able to sense that it has a reasonable chance of gaining a foothold from a flying approach. While the portions between the slots may suffice for retention, it is an awkward maneuver to initially attain, even for the clinging birds, especially since they must make an aerial landing and grasp a small slit on a flush surface in order to utilize it. This is a difficult and discouraging arrangement and is further complicated by the fact that there is food within or protruding from the very slots they must quickly grip to acquire a secure attachment. The arrangement proposed by Lynch also brings the bird's foot into contact with the feed allowing the transfer of bacteria to the food source.
U.S. Pat. No. 4,318,364 by Besherer demonstrates curved shaped channels that act to dispense food universally to any bird. There is no device or intent to discriminate between the assortment of wild birds. The device merely acts to act as a conduit to release the seed from the container compartment to an exposed feeding area.
U.S. Pat. No. 4,706,851 by Hegedus demonstrates a device that, likewise, is simply another apparatus that invites and accommodates any and all birds to partake of the available seed from long perches adjacent to the dispensing apertures.
U.S. Pat. No. 4,996,947 by Petrides is a clever and effective method that requires a bit of acrobatics from its participants. The concept and design requires that a bird, such as the adaptable goldfinch or pine siskin easily land on a comfortable perch and then swing upside down to reach an opening in the feeder that is directly below the perch. While this technique excludes the house sparrow and house finch that are not as gymnastic, it is based upon entirely different principles and design.